University of California, Berkeley: Paul Hilfinger's "Types"
Read slides 2 through 14 and use them as a review or supplement to the above readings. Slides 15 through 31 give examples of type inference for the languages Prolog, Java, and Python.
Click http://web.archive.org/web/20160502144528/http://inst.eecs.berkeley.edu/~cs164/sp11/lectures/lecture17.pdf link to open resource.